modes/ctr128.c: fix false carry in counter increment procedure.
authorAndy Polyakov <appro@openssl.org>
Sun, 20 Nov 2016 22:38:12 +0000 (23:38 +0100)
committerAndy Polyakov <appro@openssl.org>
Fri, 25 Nov 2016 16:22:21 +0000 (17:22 +0100)
GH issue #1916 affects only big-endian platforms. TLS is not affected,
because TLS fragment is never big enough.

Reviewed-by: Matt Caswell <matt@openssl.org>
crypto/modes/ctr128.c

index b7ffb73..03920b4 100644 (file)
@@ -52,7 +52,7 @@ static void ctr128_inc_aligned(unsigned char *counter)
         --n;
         d = data[n] += c;
         /* did addition carry? */
-        c = ((d - c) d) >> (sizeof(size_t) * 8 - 1);
+        c = ((d - c) & ~d) >> (sizeof(size_t) * 8 - 1);
     } while (n);
 }
 #endif